JSFiddle - React, Tailwind, and code Playground

HTML

<body>
         <div id="box">
         		<p>(Maximum Allowed Characters : 160)</p>
         		<p><textarea id="area" rows="10" cols="40"></textarea></p>
         		<span id="message"> 160 </span> Characters Remaining
         		<input type="button" id="tweet" value="Tweet"/>
         </div>

         
  <body>

CSS

#box{
        	width:400px;
        	height:230px;
        	background-color: pink;
        	margin:50 auto 0;
        	padding-top:20px;
        	padding-left:40px ;
        }

        p{
          margin: 0;
        }

        #area{
        	margin-bottom: 10px;
        }

        #tweet{
        	margin-left: 130px;
        }

        .minus{
        	color: red;
        }

JavaScript

$(document).ready(function(){
           	   $("#tweet").attr("disabled","disabled");
           	   $("#area").keyup(function(){
           	   	  var chars=$(this).val().length;

           	   	  $("#message").text(160-chars);
           	   	  
           	   	  if(chars > 160 || chars <=0){
                      $("#tweet").attr("disabled","disabled");
                      $("#message").addClass("minus");
                      $(this).css("text-decoration","line-through");
                      
           	   	  }else{
           	   	  	$("#tweet").removeAttr("disabled");
           	   	  	$("#message").removeClass("minus");
           	   	  	$(this).css("text-decoration","");
           	   	  }
           	   });
           });